System for intelligent lubrication control in mechanical high-speed gearboxes

Abstract

A system for intelligent lubrication control in a high-speed mechanical transmission, the system comprising: a transmission housing enclosing a plurality of meshing gears mounted on rotating shafts and supported by bearing units; a plurality of sensor units physically mounted at predetermined locations within the transmission housing near gear engagement surfaces, bearing raceways, and shaft journals, each sensor unit comprising at least one temperature sensor, at least one vibration sensor, and at least one speed sensor, as well as an associated signal conditioning circuit configured to generate conditioned electrical signals representing operating parameters;a data acquisition module electrically connected to the plurality of sensor units and comprising an analog-to-digital conversion circuit configured to digitize the processed electrical signals; a hardware-based control unit comprising a microcontroller, a field-programmable gate array, and associated memory and input / output circuitry, wherein the control unit is configured to receive the digitized signals and generate control outputs based on predetermined threshold conditions; a lubricant supply system comprising a variable displacement pump driven by an electromechanical actuator, a plurality of electronically actuated microvalves arranged along a distributed lubricant network, and a plurality of lubrication channels formed in the gearbox housing and terminating at targeted lubrication points;and a multitude of flow control nozzles configured to direct lubricant to selected areas of the multitude of meshing gears and bearing units, the control unit being electrically coupled to the variable displacement pump and the multitude of electronically actuated microvalves to control lubricant flow rate, pressure and distribution depending on the operating parameters.

Description

AREA OF INVENTION The present disclosure relates generally to mechanical transmission technology and in particular to a system integrated into a high-speed transmission that dynamically controls the lubrication parameters in real time based on the operating conditions. The disclosure further relates to electromechanical control architectures integrated into transmissions, bearing assemblies, and shaft drives to increase lubrication efficiency, reduce wear, and improve operational reliability at high speeds and varying loads. BACKGROUND OF THE INVENTION High-speed transmission systems, including gearboxes, turbine-driven shafts, automotive powertrains, and industrial rotary machinery, operate under extreme conditions characterized by high rotational speeds, fluctuating torques, and temperature gradients. Conventional lubrication systems in such systems typically rely on constant-flow oil circulation or passive splash lubrication, which cannot adapt to dynamic variations in operating parameters. These traditional approaches often result in either under-lubrication, leading to excessive friction and premature wear, or over-lubrication, causing energy losses, increased turbulence, and thermal inefficiencies. Furthermore, existing lubrication systems lack local control and fail to account for spatial variations in stress, temperature, and vibration across different transmission components.Therefore, there is a need for an intelligent, adaptive lubrication system that can monitor and precisely control lubricant distribution in high-speed systems in real time. High-speed transmission systems such as industrial gearboxes, turbine drives, and automotive transmissions are subjected to extreme operating conditions characterized by high rotational speeds, high contact stresses, and continuous temperature fluctuations. Under these conditions, effective lubrication is crucial to maintain the formation of a hydrodynamic or elastohydrodynamic lubricating film between the contact surfaces, thereby reducing friction, minimizing wear, and preventing failures. Traditional lubrication methods in these systems primarily include immersion lubrication, oil bath lubrication, and central pressure lubrication. In immersion lubrication, rotating components such as gears are immersed in a lubricant reservoir and distribute the oil to the adjacent surfaces by centrifugal force.While this method is simple and inexpensive, it is inaccurate and highly dependent on rotational speed, often leading to uneven lubrication at low speeds or during transient operating conditions. Oil bath lubrication also provides passive immersion lubrication of the components, but it cannot account for local thermal hotspots or variable load conditions in different areas of the gearbox. Forced lubrication systems, which use pumps to circulate lubricant through predefined channels, represent a more controlled approach and are frequently used in high-performance applications. These systems typically include a fixed-volume pump, pressure relief valves, and a network of oil channels to supply lubricant to critical components. However, such systems generally operate at predefined flow rates and pressures without adapting in real time to dynamic changes in load, speed, or temperature. This often results in excess lubricant being directed to areas of low demand, leading to turbulence losses and increased self-consumption, while simultaneously providing inadequate lubrication to highly stressed areas under peak conditions.Furthermore, conventional forced lubrication systems are based on limited measuring mechanisms that typically restrict themselves to measuring oil temperature and pressure and do not detect local phenomena such as micro-wear, vibration-induced stresses, or short-term temperature spikes at the gear transitions. Recent developments have introduced electronically controlled lubrication systems with basic sensors and programmable controllers for pump control. These systems can adjust lubrication parameters based on temperature or speed sensors, thus offering a degree of flexibility. However, such implementations are often limited by the low spatial resolution of the sensors, delayed response times, and reliance on centralized control strategies that fail to account for distributed variations within the gearbox. Furthermore, many existing solutions rely heavily on software-driven control algorithms running on general-purpose processors. This can introduce latency and reduce determinism in time-critical lubrication adjustments, particularly in high-speed applications where a rapid response is essential. Another limitation of current systems is the lack of precise metering mechanisms capable of directing lubricant precisely to specific micro-areas within the gearbox. Conventional nozzle and channel designs are static and do not dynamically adjust flow direction and intensity, resulting in inefficient lubricant utilization. Furthermore, existing systems often lack closed-loop control at the lubricant delivery point, making it impossible to verify the actual effectiveness of lubricant distribution. This lack of local feedback can lead to undetected lubricant failures and, consequently, accelerated component wear. Despite incremental progress, existing lubrication technologies for high-speed mechanical transmissions still suffer from limitations in adaptability, measurement accuracy, inefficient lubricant distribution, and limited real-time control capabilities. These drawbacks underscore the need for a more advanced, integrated system with intelligent, localized, and responsive lubricant control to meet the demands of modern high-speed mechanical applications. SUMMARY OF THE INVENTION This disclosure describes a system integrated into a mechanical transmission structure that intelligently controls the lubricant supply based on acquired mechanical and thermal parameters. The system comprises several sensor modules integrated at critical, load-bearing interfaces such as gear engagement zones, bearing housings, and shaft bearings. Each sensor module generates electrical signals representing parameters such as temperature, rotational speed, vibration amplitude, and contact voltage. These signals are transmitted to a central control unit, which features a hardware-based processing architecture with signal conditioning circuits, analog-to-digital converters, and a programmable logic controller (PLC).The control unit processes the conditioned signals to determine the local lubricant requirement and dynamically controls several microvalve assemblies and variable displacement pumps arranged along a distributed lubrication network. The system also includes flow control channels and directional nozzles that precisely deliver the lubricant to the target areas within the gearbox, ensuring optimal lubrication coverage under varying operating conditions. The present invention aims to improve the operational reliability and efficiency of high-speed mechanical gearboxes by means of an integrated lubrication control system that dynamically responds to changing mechanical and thermal conditions. One objective of the invention is the real-time monitoring of critical operating parameters such as temperature, vibration, speed, and contact stress at multiple localized areas within a gearbox. This enables precise determination of the lubricant requirements at gear transitions, bearing surfaces, and shaft bearings. A further objective of the invention is to provide a hardware-integrated control architecture configured to process acquired parameters and generate deterministic control signals for regulating lubricant flow, pressure, and distribution without relying on non-deterministic processing environments. The invention further aims to achieve localized and targeted lubricant delivery through a network of controllable flow channels and actuators, thereby minimizing over-lubrication, reducing turbulence losses, and improving the energy efficiency of the transmission system. A further objective of the invention is the adaptive control of lubricant supply in response to temporary load changes and temperature gradients, in order to ensure the maintenance of an optimal lubricating film in both steady-state and dynamic operation. The invention also aims to provide a closed-loop control system that monitors the lubricant supply in critical contact areas, thereby enabling real-time corrections and reducing the risk of lubricant failure. A further objective of the invention is the integration of the lubrication control components into a compact, modular device structure that can be mechanically connected to a variety of transmission assemblies. This facilitates the installation, scalability, and retrofitting of existing systems. The invention also aims to extend the service life of the components, reduce maintenance frequency, and improve overall system durability by minimizing wear, friction, and thermal stress through intelligent lubrication management. BRIEF DESCRIPTION OF THE DRAWING These and other features, aspects and advantages of the present invention will be better understood if the following detailed description is read with reference to the accompanying drawing, in which the same symbols represent the same parts: Fig. 1 shows a block diagram of an intelligent lubrication control system in a high-speed mechanical transmission assembly. Furthermore, those skilled in the art will recognize that the elements in the drawing are simplified and not necessarily drawn to scale. For example, the flowcharts illustrate the process by highlighting the main steps to facilitate understanding of the present disclosure. With regard to the construction of the device, one or more components may be represented in the drawing by conventional symbols. The drawing may show only those specific details relevant to understanding the embodiments of the present disclosure, so as not to clutter the drawing with details that are already apparent to those skilled in the art from the description contained herein. DETAILED DESCRIPTION OF THE INVENTION To facilitate understanding of the principles of the invention, reference is made below to the embodiment shown in the drawing, which is described using specific terms. It is understood, however, that this does not limit the scope of protection of the invention. Rather, modifications and further developments of the depicted system, as well as further applications of the inventive principles shown therein, are conceivable, insofar as they would normally occur to a person skilled in the art in the field of the invention. It will be clear to those skilled in the art that the foregoing general description and the following detailed description are exemplary and explanatory of the invention and are not to be understood as a limitation of it. References to “an aspect”, “another aspect”, or similar phrases in this description mean that a particular feature, structure, or property described in connection with the embodiment is included in at least one embodiment of the present disclosure. Therefore, phrases such as “in one embodiment”, “in another embodiment”, and similar expressions in this description may, but do not necessarily, all refer to the same embodiment. The terms "includes," "comprehensive," or similar expressions denote non-exclusive inclusion. Thus, a procedure or method containing a list of steps does not only include those steps but may also include further steps not explicitly listed or inherent in the procedure or method. Likewise, the statement "includes..." for one or more devices, subsystems, elements, structures, or components, without further limitations, does not preclude the existence of other devices, subsystems, elements, structures, or components. Unless otherwise defined, all technical and scientific terms used herein have the same meanings generally known to those skilled in the art in the field to which this invention belongs. The systems, methods, and examples described herein serve only for illustration and are not to be understood as limiting. Embodiments of the present disclosure are described in detail below with reference to the attached drawing. Fig. 1 shows a block diagram of an intelligent lubrication control system in a high-speed gearbox. The system comprises: a gearbox housing 102 with several meshing gears mounted on rotating shafts and supported by bearing units; several sensor units 104 located at predetermined positions in the gearbox housing near gear meshing surfaces, bearing raceways, and shaft journals.Each sensor unit comprises at least one temperature sensor, at least one vibration sensor, and at least one speed measuring element, as well as an associated signal conditioning circuit for generating conditioned electrical signals representing operating parameters; a data acquisition module 106, which is electrically connected to the sensor units and includes an analog-to-digital conversion circuit for digitizing the conditioned electrical signals; and a hardware-based control unit 108 with a microcontroller, an FPGA (field-programmable gate array), and associated memory and input / output circuitry. The control unit receives the digitized signals and generates control outputs based on predetermined thresholds.a lubricant supply system 110, comprising a variable displacement pump 112 driven by an electromechanical actuator, several electronically actuated microvalves arranged along a distributed lubricant network, and several lubrication channels formed in the gearbox housing and terminating at the designated lubrication points; and several flow control nozzles 114 configured to direct lubricant to selected areas of the meshing gears and bearing units, the control unit being electrically coupled to the variable displacement pump and the electronically actuated microvalves to control lubricant flow rate, pressure, and distribution depending on the operating parameters. In one embodiment, each sensor unit 104 further comprises a strain gauge 116 configured to detect localized mechanical stresses at predetermined locations, and the signal conditioning circuit includes amplification and filter stages for noise reduction and signal normalization. In one embodiment, the data acquisition module 106 further comprises a multiplex circuit configured to sequentially sample signals from the numerous sensor units and forward the sampled signals to the analog-to-digital conversion circuit. In one embodiment, the hardware-based control unit comprises 108 special comparator circuits and time modules configured to execute deterministic control logic for real-time control of the lubricant supply system. In one embodiment, the variable displacement pump 112 comprises a lifting mechanism coupled to the electromechanical actuator, wherein the actuator is configured to vary the pump output according to the control signals received from the control unit. In one embodiment, each of the numerous electronically actuated microvalves comprises an electromagnetically driven valve element configured to selectively open or close a corresponding lubrication channel. In one embodiment, the lubrication channels are integrally formed in the gearbox housing as internal lines extending from the lubricant supply system to the intended lubrication points. In one embodiment, the system further comprises a plurality of flow sensors and pressure sensors 116 arranged along the distributed lubricant network. The sensors are electrically coupled to the control unit to provide feedback signals indicating the lubricant supply conditions. In one embodiment, the system further comprises a thermal management module 118 with a heat exchanger and a temperature-controlled lubricant reservoir. The thermal management module is operationally coupled to the lubricant supply system to control the lubricant temperature. In one embodiment, the hardware-based control unit 108, the data acquisition module 106 and the lubricant supply system 110 are housed in a modular enclosure which is mechanically connected to the gearbox housing, thus forming an integrated lubrication control device. The described system is fully implemented using physically integrated electromechanical and electronic components located within and on the gearbox unit to ensure direct operability without abstract or non-physical constructs. The sensor units include discrete temperature sensors, vibration transducers, speed sensors, and strain gauges. These are manufactured as either semiconductor or electromechanical devices and generate measurable electrical output signals depending on physical conditions. The output signals are processed by analog signal conditioning circuits consisting of operational amplifiers, resistive-capacitive filters, and voltage normalization stages. The data acquisition module incorporates hardware-based multiplexers and analog-to-digital converters as integrated electronic circuits that convert continuous electrical signals into discrete digital representations.The control unit consists of a microcontroller, programmable logic circuits, comparator circuits, clocked time modules, and memory elements. All components are implemented as physical semiconductor devices on printed circuit boards and interconnected via conductive traces. The lubrication system includes a mechanically driven variable displacement pump with a controllable stroke mechanism, actuated by an electromechanical actuator, as well as electromagnetically actuated microvalves that control the fluid flow through internal lubrication channels in the gearbox housing. Flow and pressure sensors are integrated into the lubrication network as physical measuring devices. The thermal management module includes a heat exchanger and a conductive storage device that enables controlled heat transfer.All components are structurally mounted, electrically interconnected, and arranged in such a way that they ensure real-time lubricant control through direct physical interactions, thus guaranteeing full functionality through a hardware-based implementation. In one embodiment, the system is physically integrated into a high-speed gearbox. This gearbox consists of a housing that encloses several meshing gears on rotating, bearing-supported shafts. The lubrication control system comprises a network of embedded sensors arranged at predetermined positions within the housing, particularly near gear teeth, bearing raceways, and shaft journals. Each sensor consists of at least one temperature sensor, one vibration sensor, and one speed sensor. These sensors are electrically connected to a signal conditioning circuit that amplifies, filters, and normalizes the raw sensor data. The processed signals are forwarded to a central processing module housed in a protective enclosure on the gearbox casing. This processing module comprises a hardware-based control architecture with a microcontroller, an FPGA (Field-Programmable Gate Array), and dedicated analog processing circuits for executing deterministic control logic. The control architecture continuously evaluates input signals and generates control outputs based on predefined threshold conditions and adaptive, hardware-implemented control algorithms. A lubricant supply system is coupled to the control module and consists of a variable displacement pump with an electric actuator, several electronically actuated microvalves, and a lubrication channel network integrated into the gearbox housing. Each microvalve is positioned along a lubrication line leading to a target lubrication point, such as a gear fit or a bearing surface. The control module selectively actuates the microvalves and modulates the pump output to regulate lubricant flow and pressure in real time. In one embodiment, the system further comprises a thermal management interface with heat exchangers and temperature-controlled containers, wherein the control module adjusts the lubricant temperature depending on the detected thermal conditions. Additionally, a control loop is established in which downstream flow and pressure sensors confirm the lubricant supply in real time, thus enabling closed-loop control of the lubrication process. The system also includes a design in which the lubrication control components are integrated into a modular lubrication control unit that is mechanically connected to the gearbox housing. The unit consists of a rigid housing that supports the sensor modules, the control electronics, the pump unit, and the lubricant distribution network, thus forming a self-contained lubrication control system that can be adapted to various gearbox architectures. The system is integrated into a high-speed gearbox whose housing encloses meshing gears on rotating, bearing-supported shafts. An integrated lubrication control system is mechanically connected to the housing. Several sensor units are mounted at predetermined locations, including gear engagements, bearing raceways, and shaft journals. Each sensor unit incorporates temperature, vibration, and speed sensors, as well as strain gauges at specific locations to detect local stresses. Each sensor unit is electrically connected to a signal conditioning circuit comprising amplifier stages, bandpass and lowpass filters, and offset correction elements. This generates normalized analog signals with reduced noise and improved dynamic range. The processed signals are then transmitted to a data acquisition module with a multiplexer.This module sequentially samples the outputs of the sensor units and forwards the sampled signals to an analog-to-digital conversion circuit. This generates time-synchronized digital representations of the measurement parameters. The digitized signals are fed into a hardware-based control unit, which includes a microcontroller, an FPGA (Field-Programmable Gate Array), and associated memory and input / output circuitry for executing deterministic control operations. Within the control unit, a sequence of processing stages is implemented in hardware logic to minimize latency and ensure predictable timing under high-speed conditions. In a first step, the incoming digitized signals are calibrated and normalized using stored calibration coefficients assigned to each sensor to compensate for sensor-specific offsets and gain variations. Feature extraction then takes place in a subsequent step.Derived parameters such as temperature change rate, vibration spectral energy in predefined frequency bands, rotational acceleration and voltage gradients are calculated using fixed-point arithmetic units and digital filter blocks in the programmable logic. The control unit then determines a lubricant requirement index for each monitored area. This index is calculated using a deterministic mapping function that combines the extracted features with predefined thresholds and weighting coefficients from memory. The mapping function is implemented in hardware using comparator circuits, lookup tables, and arithmetic accumulators, thus avoiding dependence on non-deterministic software execution. The lubricant requirement index corresponds to a quantized control value that specifies the required lubricant flow and pressure for the respective area. A scheduling module in the control unit prioritizes lubricant requirements across multiple areas based on severity metrics derived from the lubricant requirement indices, ensuring that areas with high loads or high temperatures are supplied promptly. Based on the calculated lubricant demand indices, the control unit generates control signals to operate a lubricant delivery system. This system consists of a variable displacement pump driven by an electromechanical actuator and several electronically actuated microvalves arranged along a distributed lubricant network. The pump output is regulated via a stroke mechanism, in which the actuator position is adjusted in discrete steps according to the total lubricant demand of all monitored areas. Simultaneously, individual microvalves, each containing an electromagnetically actuated valve element, are selectively controlled to open or close corresponding lubrication channels in the gearbox housing. The channels terminate in flow control nozzles directed at the target lubrication points, including gear meshing areas and bearing contact surfaces. This enables targeted and localized lubricant delivery. A closed-loop control system is implemented using multiple flow and pressure sensors arranged along the lubrication network. These sensors generate feedback signals representing the actual lubricant flow conditions, which are then fed back to the control unit via the data acquisition module. The control unit compares these feedback signals with the target values ​​derived from the lubricant demand indices using hardware comparators. Any deviation exceeding the permissible tolerance limits triggers adjustments to the pump delivery rate and valve actuation. This feedback-driven control ensures that the specified lubricant quantities are precisely achieved at each target point. The system also includes a thermal management module with a heat exchanger and a temperature-controlled lubricant reservoir. The control unit regulates the lubricant temperature by controlling the flow through the heat exchanger based on measured thermal conditions. The integration of sensor, control, and actuator components into a modular housing, mechanically connected to the gearbox housing, creates a compact and self-contained lubrication control system. This architecture enables continuous, real-time adjustment of lubrication parameters to dynamic operating conditions. This maintains optimal lubricant film properties, reduces friction and wear, and increases the service life and efficiency of the gearbox. The drawing and the preceding description illustrate embodiments. Those skilled in the art will recognize that one or more of the described elements can be combined to form a single functional element. Alternatively, certain elements can be divided into several functional elements. Elements of one embodiment can be added to another. For example, the process flows described here can be modified and are not limited to the manner described herein. Furthermore, the actions of a flowchart need not be performed in the sequence shown; nor do all actions necessarily need to be carried out. Actions that do not depend on other actions can be performed in parallel with the other actions. The scope of protection of the embodiments is in no way limited by these specific examples. Numerous variations, whether explicitly stated in the description or not, such as...Differences in structure, dimensions, and materials are possible. The scope of protection of the embodiments is at least as comprehensive as described by the following claims. The advantages, other benefits, and problem solutions have been described above with reference to specific embodiments. However, the advantages, benefits, problem solutions, and any components that can effect or enhance an advantage, benefit, or solution are not to be construed as critical, necessary, or essential features or components of the claims. REFERENCES 100 A system for intelligent lubrication control in a mechanical high-speed transmission assembly. 102 Gearbox housing. 104 Multiple sensor units. 106 Data acquisition module. 108 Hardware-based control unit. 110 Lubricant supply system. 112 Variable displacement pump. 114 Multiple flow control nozzles. 116 Strain gauge. 118 Thermal management module.

Claims

A system for intelligent lubrication control in a high-speed mechanical transmission, the system comprising: a transmission housing enclosing a plurality of meshing gears mounted on rotating shafts and supported by bearing units; a plurality of sensor units physically mounted at predetermined locations within the transmission housing near gear engagement surfaces, bearing raceways, and shaft journals, each sensor unit comprising at least one temperature sensor, at least one vibration sensor, and at least one speed sensor, as well as an associated signal conditioning circuit configured to generate conditioned electrical signals representing operating parameters;a data acquisition module electrically connected to the plurality of sensor units and comprising an analog-to-digital conversion circuit configured to digitize the processed electrical signals; a hardware-based control unit comprising a microcontroller, a field-programmable gate array, and associated memory and input / output circuitry, wherein the control unit is configured to receive the digitized signals and generate control outputs based on predetermined threshold conditions; a lubricant supply system comprising a variable displacement pump driven by an electromechanical actuator, a plurality of electronically actuated microvalves arranged along a distributed lubricant network, and a plurality of lubrication channels formed in the gearbox housing and terminating at targeted lubrication points;and a multitude of flow control nozzles configured to direct lubricant to selected areas of the multitude of meshing gears and bearing units, the control unit being electrically coupled to the variable displacement pump and the multitude of electronically actuated microvalves to control lubricant flow rate, pressure and distribution depending on the operating parameters. System according to claim 1, wherein each sensor unit further comprises a strain gauge configured to detect localized mechanical stresses at predetermined locations, and the signal conditioning circuit comprises amplification and filter stages for noise reduction and signal normalization. System according to claim 1, wherein the data acquisition module further comprises a multiplex circuit configured to sequentially sample signals from the plurality of sensor units and forward the sampled signals to the analog-to-digital conversion circuit. System according to claim 1, wherein the hardware-based control unit comprises dedicated comparator circuits and timing modules configured to execute deterministic control logic for real-time control of the lubricant supply system. System according to claim 1, wherein the variable displacement pump has a lifting mechanism coupled to the electromechanical actuator, wherein the actuator is configured to vary the pump output according to the control signals received from the control unit. System according to claim 1, wherein each of the numerous electronically actuated microvalves comprises an electromagnetically driven valve element configured to selectively open or close a corresponding lubrication channel. System according to claim 1, wherein the lubrication channels are integrally formed in the gearbox housing as internal lines extending from the lubricant supply system to the intended lubrication points. The system according to claim 1 further comprises a plurality of flow sensors and pressure sensors arranged along the distributed lubrication network, wherein the sensors are electrically coupled to the control unit to provide feedback signals indicating the lubricant supply conditions. System according to claim 1, further comprising a thermal management module with a heat exchanger and a temperature-controlled lubricant reservoir, wherein the thermal management module is operationally coupled to the lubricant supply system to control the lubricant temperature. System according to claim 1, wherein the hardware-based control unit, the data acquisition module and the lubricant supply system are housed in a modular enclosure which is mechanically connected to the gearbox housing and thus forms an integrated lubrication control device.

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